The power-transforming devices, especially adapters, are generally used in many kinds of machines and electric apparatuses, such as the radios, CD players, printers, and notebook computers. They need adapters to transform AC input powers into appropriate DC output powers having different voltages to fit their different uses. FIG. 1 is a conventional adapter having an adapter body 11, an electric wire 12, a DC plug 13, and an AC plug 14. The AC power inputted from the AC plug 14 is transformed into a DC power in the adapter body 11, and the DC power is outputted from the DC plug 13 through the electric wire 12 into machines and electric apparatuses. FIG. 2 is another conventional adapter which is often used in a notebook computer. The adapter body 22 is still used for transforming an AC input power into a DC output power, and the DC power is still outputted from the DC plug 24 through the electric wire 23 into the notebook computer. Differently, the AC plug 21 is extractably mounted in a jack 25 of the adapter body. When the adapter is not in use, the AC plug 21 can be pulled out of the jack 25, but the AC plug 21 is connected to jack 25 only when the adapter is in use. Because the AC plug can be extracted from the adapter, this adapter is more convenient to be packed up and carried. This advantage is especially important to the notebook computer.
However, these two conventional adapters still have many limitations and disadvantages as follows:
1. The DC plug is connected to the adapter body so that the adapter is not truly convenient to be carried. PA1 2. The electric wire is connected to the adapter body so that it is not easy to coil up the wire. PA1 3. Because the forms of the AC and DC plugs have to be altered with different power-consuming and power-supplying systems and the plugs are connected to the adapter bodies, the adapter bodies have to be changed accordingly while the systems are changed. Therefore, not only is the using efficiency of the adapter bodies dropped but the production cost of the assembled system is increased.